降解菌HN36对二氯喹啉酸胁迫下烟草茎尖和叶片超微结构的影响

 利用降解菌HN36降解土壤中的二氯喹啉酸及修复土壤的生态环境, 为稻田植烟地区烟叶安全生产提供技术和理论依据。采用盆栽试验, 将二氯喹啉酸与降解菌HN36配成一定量的溶液, 均匀喷洒到过筛的干土中, 将5叶期烟苗移栽到处理的塑料盆土中。当烟苗长到8叶期时分别取茎尖﹑顶叶和中部叶进行处理, 在电镜下观察细胞超微结构变化, 利用高效液相色谱仪检测土壤中二氯喹啉酸降解的动态。烟株细胞超微结构变化的程度有差异, 表现为受害烟株>修复烟株>健康烟株; 烟株的茎尖和顶叶细胞伤害最严重, 中部叶片细胞伤害较轻。研究结果还显示, 在含二氯喹啉酸的土壤中, 加入降解菌HN36能加速二氯喹啉酸降解, 改善土壤健康质量, 烟株细胞超微结构及烟叶品质明显得到修复。

Effect of degrading bacterium HN36 on ultrastructure of flue-cured tobacco stem and leaves under quinclorac stress

Aims Our objectives were to determine (a) the effects of quinclorac-degrading bacterium on ultrastructure of tobacco stem and leaves in quinclorac-contaminated soil and (b) the degradation of quinclorac in soil after bacterium HN36 treatment. The research will provide a theoretical basis for soil remediation by degrading bacteria and for tobacco production safety.
Methods We treated quinclorac-contaminated soil with degrading bacterium HN36 and then observed the ultrastructure of tobacco leaves using an electron microscope and determined chemical composition.
Important findings Cell ultrastructures of stem and tip leaves were more affected by quinclorac than those of middle leaves. The degrading bacterium HN36 had a positive effect on ultrastructure of tobacco leaves. The degradation of quinclorac in soil treated with the degrading bacterium was significantly faster than in untreated soil. Applying quinclorac-degrading bacterium HN36 to the soil contaminated by quinclorac could mitigate phytotoxicity of the tobacco cell ultrastructure and accelerate the degradation of quinclorac in soil.